THS in Scotland Evening Meeting

3B or not 3B? That is the questionby Dr Grant Thomson, Savante Offshore Services Ltd

Class 3B subsea laser scanning has enjoyed a renaissance in the production of high-value, asset-integrity reporting products. Photogrammetry, potentially a more flexible technique supported by emergent camera technologies, is approaching a similar measurement capability. Future IRM, construction and dim-con projects will soon need to ask the question. When should we select the laser and when photo-grammetry to solve our measurement problems?

We present some 3d models of assets using a variety of both inspection techniques to illustrate the relative value of each. We also present limited survey results using a novel Class 3B dynamic subsea laser scanner. This was used to measure the separation of buoyancy blocks supporting the catenary of a dynamic production riser without the support of third-party INS, Fibre Gyro or LBL position referencing tools.

A case study detailing the methodology decision process, planning, operational experience and successful delivery of a particularly challenging spool metrology. The spool metrology in question was hampered by vessel schedules, access constraints and a congested worksite. Subsea LiDAR was chosen as the best method to perform the metrology and delivered the required spatial information along with additional data that lead to significant savings to the project.

For accurate positioning or attitude measurements subsea typically acoustic and/or fibre optic gyro equipment is used. Quite often this equipment is relatively costly and involves time-consuming calibration procedures. Fugro has developed QuickVision, an augmented reality survey toolkit which employs cost efficient sensors that can be used operationally within minutes subsea.

All members and and non-members welcome.

A selection of cold food and drinks will be available from 18:30 and presentations will start at 19:00 prompt.

There is a charge of £10 for admission payable online during registration to cover catering (please ask at the door if you require a receipt). Admission is free for Students.